Gen light stays on

I've never been real good with the charging system or anything electrical for that matter, I have gotten my fridge to run pretty well for a 600.00 craigslist find that hadn't run for 15 years. Well, all the kids have gone back to the city after the holiday, and tomorrow I'm gonna tackle my charging problem.....
223 cu six. Red charge light on dash dims when I increase rpms but stays pretty bright, so I'm guessing I am getting something out of it. I bought a multi meter but it's still in the package and I've never used one. I have a new group 24 12 volt battery in it and the engine starts right up. What do I need to do to test the generator, or do I want to test the regulator too?. I'm not trying to keep the truck real original, so I'm kind of thinking about a gm one wire alternator in the future like I have put on my 8n tractor and a few other old trucks. For now, I just want this thing to charge so I can drive it around. Then maybe at some time I'll get plates for it. Thanks in advance.

With the idle set to factory to factory specs, the generator light will dimly illuminate when at idle speed indicating generator output is less than the electrical demand/load. In short, the battery is slightly discharging to supply the required power to meet electrical system demands in compensation for what the generator can't provide--this is normal. When the rpm is increased just past idle, the generator light should extinguish, indicating the generator is providing adequate electrical power and charging the battery. If the light remains on, the most likely cause is the voltage regulator. The voltage regulator is located on the right wheel well with a box-like lid and three contact points for the wire harness connections. Remove the lid and verify the contacts are not stuck together due to corrosion. If there is corrosion, replace the voltage regulator. Aside from damaged/cut wires, the only other possibility is a generator failure. The generators on these trucks are extremely durable. If the generator is not supplying adequate power, the most likely cause is a stuck or worn generator brush. A few gentle taps with a hammer towards the rear of the generator should free a stuck brush. If the bushes are worn, a replacement set can be obtained from your local auto parts store.

I highly recommend purchasing the factory repair manual for your truck. The manuals contain every test procedure, rebuild procedure, specification, etc. for your truck, and are the same manuals the Ford service departments used to service these trucks back in the day. An entire section is dedicated to the testing and servicing of the electrical system components alone. Used manuals can be obtained on E-bay, auto repair manual websites, etc.

I've never been real good with the charging system or anything electrical for that matter, I have gotten my fridge to run pretty well for a 600.00 craigslist find that hadn't run for 15 years. Well, all the kids have gone back to the city after the holiday, and tomorrow I'm gonna tackle my charging problem.....
223 cu six. Red charge light on dash dims when I increase rpms but stays pretty bright, so I'm guessing I am getting something out of it. I bought a multi meter but it's still in the package and I've never used one. I have a new group 24 12 volt battery in it and the engine starts right up. What do I need to do to test the generator, or do I want to test the regulator too?. I'm not trying to keep the truck real original, so I'm kind of thinking about a gm one wire alternator in the future like I have put on my 8n tractor and a few other old trucks. For now, I just want this thing to charge so I can drive it around. Then maybe at some time I'll get plates for it. Thanks in advance.

It has been years since i used the gen but if memory serves me it almost always illuminated at idle, I installed a GM 1 wire, I did need to install a second wire that tells the alternator to turn on, it has been flawless i was even able to modify the original mounting bracket, no more slow starts or parking on a hill "just in case"

Thanks for the help. I remember a couple of weeks ago I took the top of the regulator and touched a set of points together at one end of it, not the middle ones. Touching the points together made them stay closed and while closed, the red light went off. Unfortunately when I shut down the truck the red light stayed off (when ign on)so I assumed the circuit was still hot when it shouldn't be. I have a long history of buying electrical components (non returnable for good reason) and in the past seem to always buy a generator when it turned out to be the regulator and vice versa. With the regulator disconnected is there a way to just tell if the gen is putting out? I have played with brushes some, but I have kinda poor eyesight up close and my finger tips are all shot from tablesaw incidents, so getting into a generator is tough for me. Hate to go there if it's the regulator. I will buy that book, but I'd love to test it out today.

fromnwmt, don't tempt me. The napa store is open on sunday now...... And is this alternator a foot into the 'darkside'? Perhaps some sort of oxymoron when better electrical is considered 'dark'........

There is a test procedure for the generator while mounted to the engine, however I'm a little far from my service manual for reference...service manual is in California, I am in Afghanistan. If you disconnect the voltage regulator for any reason, be sure to correctly polarize the generator when reconnecting. You can check the generator brushes with a flashlight. On the rear of the generator case are two cooling slots. Look in the slots with a flashlight to see the brushes are contacting the commutator shaft and have adequate contact material remaining.

Without the service manual or instructions, I wouldn't proceed any further. If you happen to damage the generator field coils by messing around, you'll have to manufacture your own square drive tool to remove the field coil bolts. If the armature is damaged, you'll need a press to remove the front bearing. Hopefully someone will chime in with the proper test procedure as designated in the service manual.

With the correct test procedure and your voltmeter, you'll be able to troubleshoot and repair the problem quickly. There's no need to install an alternator. My original 1960 generator lasted 50 years and 142,000 miles before the generator stopped working due to stuck brushes. The OEM generator will meet all your trucks electrical requirements in a stock configuration.

Thanks guys. I ultimately decided to do some other work to the truck yesterday. The charging problem still exists and I guess I'll have to make a choice about which direction to go. Besides, I wasted an hour trying to find that multimeter. I decided to just do something simple. So far I had been running this thing on the 15 yr old plus oil in the crankcase. I had the filter and some oil, so why not change it? Everything went as planned until I found the drain hole in the pan was stripped... OK so I took a piece of 1/4" fuel hose and ran a 1/4-20 round head machine screw through it, head first into the hole, tighened the nut and good to go. Then I couldnt get the large filter gasket to stay on. I didn't realize it fell off when I went to get my freshly painted canister off my halogen shop light. I mounted it with the gasket laying on the floor. Ran the engine, oil light goes off. Oil flood under the engine. So I grease up the gasket and now good it stays on. Now I only have about 3 qts in and no other oil anywhere. So this job isn't complete either. I figured out it was ok to just back up out of the shop to mop up the floor. Big crunch as I ran over my halogen light with the right front tire....Good thing the kids left me with a little beer.

fromnwmt, don't tempt me. The napa store is open on sunday now...... And is this alternator a foot into the 'darkside'? Perhaps some sort of oxymoron when better electrical is considered 'dark'........

I hear you loud and clear next you will install intermittent wipers etc. but at the time it was my daily driver and i had just had enough I do still have my Gen so if the day comes i want to rebuild it and install

To check the generator, Their are 3 connections on the regulator they are labled gen, fld, bat. get your multi meter working check the bat it should say 12 something. Start engine after you fix your oil problem and at a fast idle it should be 13 14 something. If not, see what it says on the gen lug on the regulator it should say 13 14 something. If not keep it connected their and and carefully jump a wire across the bat and fld termernals,(do this only for a very short time only) that will put the gen in full charge you should see a voltage increase, If you do it may be the regulater if not the brushes in the generator. My truck did this and I found a broken brush spring.

Well, I got the manual and so I took off work a bit early to test the generator. I found the multimeter but it needs a 9 volt battery and it's a 24 mile round trip to town so I decided to pull the generator to inspect and clean it. At this point I went to start it up so there would be some heat in the engine compartment, but the normally reliable thing wouldn't start. I cranked and cranked.... Last thing I had done was the heater stuff, which at various times spouted all over the engine compartment so everything such as distributor was wet and all coated with antifreeze. I cleaned the dist and cap, got back in the cab and with one crank BOOM!!!!!!!!!. I mean like a 12 guage and my ears were killing me! My 2 week old muffler had exploded from raw gas from earlier cranking. OK, now back to the generator.The field wire either broke on removal or was already broken at the connection, so I thought I had it made. I dissasembled it anyway and maybe a brush had been hung up, but looked real fresh inside. I couldn't make heads or tails of the manual, but the gen was simple like you guys said. I got it all nice and when I put it back on and started the now noisy truck, the generator was making a high pitched sound, maybe I installed one of the brushes backwards? Anyway the gen light is still on. Tried to adjust the regulator a bit, but it's getting cold out there (no heat in my shop). Not sure why I keep doing this stuff. Got my first big ford exactly 40 years ago at 18 yrs old. A 29 AA. I am frustrated. I know the scientific guys and perfectionists pull everything apart and sandblast and rotisserie and rebuild. That would end some of the frustration, but it just isn't me. All of this leads into a question I have about a friend. Ya see he has this old ford and wants to put a gm one wire alternator in it, but he doesn't know what to do about the idiot light.... Should I tell him to just run the wire to the battery and the dash lighting will take care of itself, or does that have to be dealt with under the dash?

Stole a 9v from my smoke detector and fired up the multi tester. Showed 37.8 amps with the test in the service manual. Still noisy so I took it apart again and sure enough a brush in wrong way and clicking in the grooves of the armature. Now I'm off to town for a voltage regulator at napa if they have one. There is a small black wire piggybacked on the big yellow armature wire, not shown or mentioned in the book. Is it for the gen light? Wish me luck. I need it with electrical.

I'm pretty sure that smaller black one on the armature terminal goes to the horn relay. I took harnesses out of three different trucks to get the one I have so I have been all through them but it is all but gone out of my head. I would go out and look at the truck but we are in the middle of a snowstorm and it is much warmer in here by the coal stove!
Electrical really ain't no big thing. Just one wire at a time. It all looks confusing when you try to look at them all at once. Besides, if Buzzard can do it for a living, and by the way, that is what I do for a living as well, anybody can do it! LOL!

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